The overall objective of this study is to develop and test an efficient self-report instrument to measure CAM- relevant contextual factors important in healing. Such healing factors, which may include patients' beliefs and expectancies, perceptions of the patient-provider relationship, and other environmental aspects of healing, are undoubtedly complex and have typically not been addressed in trials. However, the healing context may account for much of what is known as 'placebo.' Only recently have investigators entertained the idea that the 'black box' of the placebo effect is worth understanding and enhancing in trials and in clinical settings. The best approach to a complex issue is careful and precise methodology. Our project is synergistic with the NIH Roadmap initiative, Patient Reported Outcomes Measurement Information System (PROMIS), and will use the rigorous instrument development and validation methodology of PROMIS. The first step is to develop and refine an item bank. Initial steps in developing a bank of items that may assess contextual factors in healing include a) compilation and evaluation of existing instruments and relevant questions, b) consultation with experts, and c) focus groups with individuals who participate in CAM and conventional medicine interventions, and d) item editing and refinement. The next step of instrument development will involve administering the revised item bank to 1200 persons (an internet sample of 1000 adults and 200 local patients of a CAM clinic and a conventional primary care setting) and calibrating the items using item response theory and classical test theory. This will result in a computerized adaptive testing version of the instrument, as well as a static short form, both of which maximize information while minimizing patient burden. The instrument developed in this project will be called the Healing Encounters and Attitudes List (HEAL). The final phase of the project will involve conducting initial validation studies of the HEAL. We will evaluate the convergent, discriminant, and predictive validity of the instrument in a sample of 200 patients with chronic low back pain. One hundred of these will be CAM patients participating in chiropractic manipulation or mindfulness-based stress reduction. One hundred will be conventional medicine patients who are participating in physical therapy. We will administer the CAT version of the HEAL instrument as well as conventional measures of treatment expectancy, confidence in treatment provider, psychosocial functioning, and treatment outcome measures of CLBP pain and disability. For convergent validity, the HEAL is expected to display moderate to large correlations with measures of similar constructs. The HEAL is expected to correlate modestly with self-report measures of general psychosocial functioning, in support of discriminant validity. Finally, HEAL score should account for a significant proportion of the variance in treatment outcome, supporting predictive validity. The project will directly impact methodology of intervention trials by providing a tool to measure aspects of patient-provider and treatment environment that may contribute substantially to health and well being.